It is known to remove moisture from gas in order to store such gas for use in a motor vehicle. Moisture is also removed from compressed gases for a variety of other applications. Typically, during the gas compression cycle the gas being compressed is passed over a desiccant bed which effects the removal of moisture from the gas. Eventually, the desiccant bed will saturate. A moisture sensor may be employed to detect the amount of moisture present in the gas exiting the compressor, sensing when the measured moisture content at the output of the compressor rises beyond a permissible range, above an upper limit. Alternately, a drying bed may be employed for a predetermined period of time. In either case a regeneration stage for recharging the desiccant bed is eventually required.
The technology for drying gas streams is well established. It includes absorption and condensation methods and the use of membrane separation systems. Examples of these technologies, used separately and in combination are U.S. Pat. Nos. 5,034,025; 5,071,451 and 5,240,472 as well as the prior art referred to therein.
Existing compressors of this type have employed gas drying arrangements that operate on a continuous basis, using a two-bed system. Examples of this type of technology include U.S. Pat. No. 6,117,211.
The present invention addresses the object of compressing natural gas with a reduced amount of moisture being present in the compressed gas by employing gas drying arrangements that operate on a dis-continuous basis, using a single-bed system wherein the compression of gas is eventually interrupted to allow the system to effect regeneration.
In the treatment of gas streams, de-watering processes generate extracted water that may contain traces of contaminants originating from the principal stream. In the case of natural gas, these contaminants include hydrogen sulphide, sulphur dioxide and mercaptans. Disposal of water containing contaminants of this type can be subject to environmental restraints.
The extracted water being produced cannot be released locally into the environment because of the contaminants present therein. Apart from issues relating to hazards, even trace smells of organic or sulphurous components from a natural gas stream would suggest to a consumer that a leak existed in the compressor system.
It is an object of this invention to address the convenient disposal of separated water under these circumstances.
It is a further object of this invention to minimize the release of electromagnetic radiation during operation of the compressor system.
The invention in its general form will first be described, and then its implementation in terms of specific embodiments will be detailed with reference to the drawings following hereafter. These embodiments are intended to demonstrate the principle of the invention, and the manner of its implementation. The invention in its broadest and more specific forms will then be further described, and defined, in each of the individual claims which conclude this Specification.